The present invention relates to a method for determining the eye- and/or head-position of a vehicle-user as well as to an arrangement pertaining thereto.
Use of such a method constitutes a basis for driver increase of the comfort and is indispensable as safety feature for vehicles. It is of particular significance in conjunction with virtual indications, or as a basis of an anti-glare protection installation.
With virtual indications, a virtual image containing the corresponding information is imaged to the vehicle-user by way of a corresponding optical device, for example in the windshield. The creation can take place with the assist of conventional optical devices such as glass lenses or the like, or also with the assist of holographic elements.
The anti-glare protection installation can be constructed in different ways and should serve the purpose of controlling stray light from oncoming vehicles, or of other light sources in the beam path proceeding toward the vehicle-user by corresponding darkening of the windshield, or by control of additional anti-glare protection elements. In every application the corresponding indications, respectively installations, can then be effectively controlled and without undesired side effects.
A method and arrangement of the aforementioned type are known from the DE-OS 31 38 712, in which the desired position is calvculated from the position of the parts of a vehicle seat. For that purpose, several values, for example: the longitudinal position of the seat, the inclination of the backrest and the height position of the headrest, are required, from which the desired position is determined with the aid of a computer. This method is costly, because at least three values are required in connection therewith. It is also inaccurate, because at least one of the values, namely that for the position of the headrest is not correct by reason of frequently false adjustments.
The present invention is concerned with providing a method of the aforemtnioned type, which enables in a particularly simple manner, a good determination of the eye and/or head position of a vehicle-user as well as providing a simple arrangement for carrying out this method.
The underlying problems are solved according to the present invention in that the affected position is determined on the basis of the adjusting parameters of a rear view mirror.
The rear view mirror is so positioned prior to, or during the use of the vehicle, by the driver or by associated adjusting electronics that it operates efficiently. This means, it is so adjusted that the rear image projected by the same is optimal for the vehicle-user. As an adjusting assist for the driver, a mark may be integrated into the rear mirror whereby in the case of an interior rear view mirror, for example, small cross hairs thereon are with a correct adjustment, made to coincide with a second mark in the rear window.
A determining beam results from the adjusting parameters of the rear view mirror by reason of the optical properties of the mirror and the beam is aligned with the eyes of the vehicle-user.
The seat center plane resulting from the arrangement of the vehicle seat, serves as further determining magnitude for the eye position. The seat center plane extends in the longitudinal direction of the vehicle and is disposed perpendicularly to the longitudinal and vertical axis of the vehicle. However, the position of this plane is known beforehand and does not depend on the respective vehicle-user. It is rather a constructionor design element of the vehicle, which for example, is predetermined by the position of the seat rails. In the alternative thereto, the adjustment of a further rear view mirror may be used as further determining factor.
Improvements of the method in accordance with the present invention are possible in various ways. Thus, the use of the adjusting parameters of an interior rear view mirror contains a particularly accurate indication concerning the eye position, because the interior rear view mirror normally possesses a greater magnification, respectively lesser reduction, than an outside rear view mirror and it is adjusted accurately to the respective eye position of the vehicle-user.
The alternative or additionally provided use of the parameters of an outside rear view mirror, offers in contrast thereto the advantage that such outside rear view mirrors are normally adjusted by means of motors and that from these adjustment parameters of the outside rear view mirror, an exact determination of the eye positio can be derived without additional use of special sensors for the adjustment of the outside rear view mirror.
As already mentioned above, the parameters from which the desired position can be determined by reason of simple geometric considerations, can be obtained with the assistance of possibly already present control elements and sensors for equipment components of the motor vehicle, such as outside rear view mirror and vehicle seat. However, it is also possible without these present devices to obtain the desired informations with low expenditures. For that purpose a potentiometer with two degrees of freedom which is very troublefree, can be used to pick up the position of the respective rear view mirror and transmits the same to a suitable control unit for the respective application.
With such a control, the desired adjusting values for the respective parts, such as for example, the height adjustment of a safety belt deflection point, the adjustment of air guide nozzles of a heating/air conditioning system, etc., as also disclosed, for example, in the aforementioned DE-OS No. 31 38 712, can be taken or fetched from tables and can be converted into corresponding predeterminations for adjusting these parts.
It is also possible to undertake a vehicle-user identification on the basis of the adjusting parameters of the rear view mirror and to fetch corresponding stored adjusting values analogous to the known memory devices. Compared to such known arrangements, the possibility of errors from an individual manual selection of the stored adjusting values can then be avoided.